Blinds of early days were controlled through cords where a switching controller was installed at one end of the track located on top of a blind. A bead chain or a cord was handing down from the switching controller to lift or lower the blind by pulling the bead chain. However, accidents of strangling small children by the bead chains have been occurred, therefore, blinds with bead chains have been forbidden in many countries. Hence, cordless blinds become household necessities. Even though there are many different designs of cordless blinds, the switching operation is not as convenient as blinds with cords.
The major issues of conventional cordless blinds are the slats only can fully open or fully close and conventional cordless blinds can not be stopped at any position according to user needs. Furthermore, the stopping control device of a cordless blind is customized and is designed and manufactured according to the weight and dimension of a cordless blind. If stopping control device does not match with the cordless blind, the cordless blind will either suddenly drop to hurt someone below or completely lift without fully close. Moreover, when the stopping control device of a cordless blind is worn after used in years, the elastic element of the force-return mechanism becomes fatigued leading to always fully close of the cordless blind.